Chow Chow's are gorgeous! I know they must be socialized heavily while young to avoid problems when older. I think she will be fine with Roxie since they are growing up together!
But they definitely need more firm and consistent training than most dogs. I would be sure to take her to training classes while she's still young. They can also be sensitive to really hot weather.
Here's a Chow Chow forum where you can probably find a lot
ChowChow.org • Index page